This flange with an O-ring seal fits the tube for the 6 Watertight Enclosure. Comes with O-rings.
O-Ring Flange (6 Series)
O-Ring Groove Design Global O-Ring and Seal
Paul's Homemade Underwater Video Housing
O-ring Flange for Custom Underwater Housings
Radial O-ring Feedthroughs High Pressure Wire Feedthrough to 15k PSI
Seal Housings and Connectors - Mechanical Research & Design, Inc
O-ring Flange for Custom Underwater Housings
O-ring Flange for Custom Underwater Housings
O-Ring Flanges – FieldWerx
Canitu O-ring Exhaust Manifold for Honda CR125
O-Ring Flange (4 Series)
Replacing Push Button O-Rings on an Ikelite Underwater Housing
The manifold O ring grooves replaces the factory for Honda flange and seals the pipe to the motor, reduce the use of sealants and keeps the front of
Canitu O-ring Exhaust Manifold for Honda CR125, Motorcycle Manifold O-ring Grooves Replaces Seal the Flange (1990-2002)